I agree. I have used it before too. I even put a layer of resin over the fleck stone to help it keep longer. Came out nice actually.idk any sealer you want to use! who cares just if you try to use primer first, the mdf will soak it right up.
and as i said before, use fleckstone! it is a ton easier to use due to only needing one coat or so, and you wont have to worry about missing a little here or there. it is a good goof off paint, you dont need to do much special to make it look good